hiram no rto n



@uiten faire* strat 'fitta Lesers .Patent No. 75,569, daad Match17,1868.

IMPROVEMENT I N DOOR-LOOKS.

@It Satanic referrer tu im tinte tcttett ttent mit mating ,pnt at ttesmut.

TO ALL WHOM ITl MAY CONCERN:

Be it known thatvI, HIRAM NRo-N, Aoi' Deltoni, in the county of Sauk,and State of Wisconsin, have invented a new and improved CombinationDoor-Lock; and I do hereby declare'that the following is a full,

, clear, and exact description thereof, which will enable those skilledin the art to make and-use the same, refer- `ence being had to theaccompanying drawings, forming part of this specification, in which-Figure 1`is'a side view of the internal mechanism of the lock.

Figure 2 is a cross-section of the same thronghthe line a: c, tig-1.

Figure 3 is a detail section of the bolts, showing the principle of thekeys action;

Similar letters` of'reference indicate corresponding parts.

This invention refers to an improved method of constructingcombination-locks for doors, drawers, Ste.,

and consists of two or more independent tumblers, which are hung by apivot-pin, at a middle point, and are operated by a verysmall key. Theselatch-es catch into notches on the bolt, thus preventing the movement ofthe latter, as will be more fully set forth.

In the drawings, A is a metallic plate, having a top, bent up as shown,and sides O C. The front plate of vthe lock is removed, it being simplya plate screwed on in the usual way. The latches are shown at a, beingpivoted to theplate by a. screw .or pin, m. l l

The ends ofthe latches are bent downwards, as shown at n'l n, for thepurpose-of catching into the notches n nw, on the bolt B, The latches,thus hung on a central pivot, are lifted by the insertion of a smallnarrow key into a slot iu thekey-hcle stud o, which projects from theplate A, under and in contact with the latches, at some point near totheincentral pivot, as shown inthe drawing.

VThe key is simplya narrow metallic vaneytting snugly in the slot in thekey-hole stud, and having its upper or actuating surface curved in anydesired manner, according to the curve of the under side of the latchesat the point where the key impinges against them, and the key oncefitted to this curve, no other will lift them, for

the slightest deviation of the false'keyfrom the proper curve will failin freeing the bolt from the latches, for it will not lift the end,.n,of one or both of them, or it will lift o'ne or both of them too much,and thus depress the end, u, into the notch 11', which will stillprevent the bolt from being withdrawn. This bolt traverses in suitableslots in the side-pieces O. C, and is held in place by studs c t', castcr set into the plate AA, all as shown.

`When the .bolt isfreed from the latches, it is thrown in or out by aknob, N, having a pin, r, projecting from` the arbor of the knob, andwhich pin strikes against the pins e e, on the bolt, as the knob isturned'right or left, whereby the bolt is moved in either direction. p

Springs s s furnish a resistingftension, to return the ends back intothe notch n when the key is withdrawn. The'key, acting upon the latchesat a point near their centres of movement, requires to be an exact fit,for the slightest variation in the shape of its curve would produce amultiplied effect at the ends of the latches, and this feature, togetherwith the smallness of the key-hole, renders it very difficult, if notimpossible, to tit a false key, or to raise the latches with picks` orother instruments. The fitting of a key by guess would be hardlypossible.

The'location 'of the key-hole near the centre of movement of the latchesadmits of the employment of a' very small key and key-hole, and thesmallness of the latter lwould render the introduction of powder, forblowing oi the lock, diilicult, or the employment of picks, to open thelock, or the introduction of any article whereby to take an impressionof the lock,also diicult, it' not wholly impossible.

By keeping the key always inserted in the lock, and providing a springto urge the bolt outward, the same can heus'ed as an ordinary latch-boltfor doors. l

I'f Va number of latches ,are used, the lock becomes proportionatelydicult to open by false means, and if the latches are sufficientlymultiplied, the lock can be made available for safe-locks. A lock withsix latches would be almost impossible to piek, or fit with a false orotherwise than with the proper key. f Itis simple,

-shown and described.

che-ap, and generally available.

I am aware that, combination-locks, opened by small curved keys, haveAbeen made, and do not claim such broadly; but.

What I claim, and desire to secure byLetters Patent, is

The employment of two or more tumblers, a, having their centre ofmovement at or near Vtheir middle points, and having then-'ends catchinginto notches n n", on the bolt B, all substantially as and for thepurpose l HIRAM NORTON. Witnesses: i

J. T. HUNrINeToN,

